How to pass the caught exception in Thread.run back to the main program?

Question

I have following three Java files (simplified from a real world application I am developing, see files at the end of this posting):
1. ThreadTest.java: The main program that invokes the Manager.run()
2. Manager.java: The manager that creates a thread to execute the Agent.run() for each agent
3. Agnet.java: The run() method can throw Exception
My goal is twofold:
1. To execute the run() method of an Agent in a thread (the reason for this is there are many Agents all managed by a Manager)
2. To catch the exception thrown by Agent.run() in the main program, ThreadTest.main() -- so the main program can alert the exceptions
My problem:
Bottomline: I cannot pass the exception thrown by Agent.run() in the Thread.run() back to the main program.
Explanation:
The signature of Thread.run() (or Runnable.run()) is
public void run();
Since it does not have a throws clause, so I have to try/catch the Agent.run(), and rethrow a RuntimeException or Error. However, this RuntimeException or Error will not be caught by the main program.
One work-around:
Subclass the ThreadGroup, override the ThreaGroup.uncaughtException() methods, and spawn the threads of this group. However, I have to duplicate the logging and exception alerts in the uncaughtException() in addition to those already in the main program. This makes the design a bit ugly.
Any suggestions? Am I doing this right?
Thanks,
Xiao-Li "Lee" Yang
Three Java Files:
// Agent.java
public class Agent {
public void run() throws Exception {
throw new Exception("Test Exception"); // Agent can throw execptions
// Manager.java
public class Manager {
public void run() throws Exception {
try {         // <===  This try/catch is virtually useless: it does not catch the RuntimeException
int numberOfAgents = 1;
for (int i = 0; i < numberOfAgents; i++) {
Thread t = new
Thread("" + i) {
public void run() {
try {
new Agent().run();
} catch (Exception e) {
throw new RuntimeException(e); // <=== has to be RuntimeException or Error
t.start();
} catch (Exception e) {
throw new Exception(e); // <== never got here
// ThreadTest.java
public class ThreadTest {
public static void main(String[] args) {   
try {
Manager manager = new Manager();
manager.run();
} catch (Throwable t) {
System.out.println("Caught!"); // <== never got here
t.printStackTrace();

Answer 1

The problem is, where could you catch it anyway?
try {
thread.start();
catch(SomeException e) {
A thread runs in a separate, er, thread, that the catch(SomeException) isn't running within. Get it?
Actually the Thread class (or maybe ThreadGroup or whatever) is the one responsible for invoking the thread's run() method, within a new thread. It is the one that would have to catch and deal with the exception - but how would it? You can't tell it what to do with it, it (Thread/ThreadGroup) is not your code.